Press apparatus for solid carbon dioxide and the like



June 14, 1938. A, SCHUTZ 2,120,943

PRESS APPARATUS FOR SOLID CARBON DIOXIDE AND THE LIKE Filed Nov. 2, 1934 5 Sheets-Sheet 1 A. scHuTz June 14, 1938.

PRESS APPARATUS FOR SOLID CARBON DIOXIDE AND THE LIKE Filed NOV. 2, 1934 5 Shets-Sheet 2 v n N h QM. Aw mfi mm June 14, 1938. Q sc u z 2,120,943

PRESS APPARATUS FOR SOLID CARBON DIOXIDE AND THE LIKE Filed Nov. 2, 1934 5 Sheets-Sheet 3 v a if. I s ww N WW m N? N. m EH 3. EH u AP N m N! h F HH v T S M U mu l ENE v I EN wu 3 H M VH I UQN Q. l I \R m WN. N. hwwf -Hk T N. H I QM Q EN n Em W M %w w \NMN N Qm QMII g m .w QE w NE E mm mvv .N w m.$ wm \WR QM mam m.- u m m uumm. MM mm. wm u mm mm. k* R. m w mu mm En NE E m. mm. I. v mw mm. Emu NM mm. m M m M H M EN QM. QM k a N June 14, 1938. sc u z 2,120,943

mass APPARATUS FOR SOLID CARBON DIOXIDE AND THE LIKE Fil ed Nov. 2; 1954 5 Sheets-Shet 4 June 14, 1938.

A. SCHUTZ PRESS APPARATUS FOR SOLID CARBON DIOXIDE MID THE .LIKE Filed Nov. 2, 1934 5 Sheets-Sheet 5 fl k Patented June 14, 1938 UNITED STATES PRESS APPARATUS FOR SOLID CARBON DIOXIDE AND THE LIKE Adolph Schutz, Wurzen, Germany, as'signor, by mesne assignments, to International Carbonic Engineering Company, Wilmington, Del.

Application November 2, 1 934, Serial No. 751,243

' In Germany November 13, 1933 37 Claims.

This invention relates to certain improvements in press apparatus for. solid carbon dioxide and the like; and the nature and objects of the invention will be readily recognized and understood by those skilled in the arts involved in the light of the following explanation and detailed description of the accompanying drawings illustrating what I at present consider to be the preferred embodiments or mechanical expressions of my H invention from among various other forms, embodiments, arrangements, combinations and constructions of which the invention is capable within the spirit and the broad scope thereof.

In the commercial production of blocks or cakes of solid carbon dioxide of-the required density for handling and efficient use, solid carbon dioxide in the formof loose crystals hereinafter referred to generically as carbon dioxide snow is compressed into the desired block or cake form by the application of mechanical pressures to the snow in asuitable type of press apparatus; and a general object of my present invention is to provide a materially improved type of such press apparatus for this purpose, in which certain of the difliculties and disadvantages encountered with the types of apparatus now in use are overcome, and with which the time required to produce the carbon dioxide blocks or cakes is materia1ly.reduced compared with the time required by'such prior apparatus.

With the types of solid carbon dioxide presses in general use, it is usually required that snow production must stop during the operation of compressing formed snow into a block, so that the next pressing operation is delayed until a sufficient quantity of snow for the next block has been formed. Considerable difliculty is also experienced with the types of solid'carbon-dioxide presses at present in use in maintaining liniform size and weight for the formed blocks or cakes of solid carbon dioxide, due to obtaining and compressing difierent quantities of ,snow in the press chamber to form the blocks, while the production time of a press is increased by the frequent-delays caused by failure of the blocks as produced to be promptly discharged from the press chamber when the chamber is opened after completion of a block therein.

One .of the main features of a solid carbon dioxide press of my invention is the provision for continuous production of carbon dioxide snow therein during and concurrently with the block compressing operations, so that block compressing is carried on without the usual delay between completion of a block and compression of the next block awaiting snow production for such next block, thereby materially increasing the block production of the press in a given period of time.

Another feature of the invention which contributes substantially to the speed of block pro-- duction and operation of the apparatus, resides in the provision for positive discharge of the compressed blocks or cakes of solid carbon dioxide from the block compressing or press cham-- ber of the apparatus into position for ready unobstructed removal from the apparatus; and this feature of the apparatus is particularly characterized by the application of mechanical pressure to a charge of snow in an upward directionand the downward movement of the press relative to the formed block to remove the block therefrom and expose it in a position for removal from the apparatus.

Another feature of the invention is found in the provision for supplying a measured charge of carbon dioxide snow to the block compressing or press chamber of the apparatus to form each block, so as to control and insure uniformity in the size and weight of the blocks produced.

The invention is further featured and characterized by a unitary operating control for the press apparatus that enables a, single operator from a central operating point to operate the apparatus through its cycle in the proper sequence, thereby rendering the apparatus in its block forming operations automatic from such single control and substantially reducing the skill and judgment required from an operator.

A further feature of the invention is found in the design of the press apparatus as of the fluid pressure actuated type, and in the arrangement of the fluid pressure actuated elements of the apparatus to reduce to a minimum heat transfer from the fluid pressure medium to the intensely cold solid carbon dioxide produced in the apparatus, in order to eliminate possibility of reducing the'temperature of the pressure medium to such a low point as to interfere with the flow thereof or cause stoppages in the fluid pressure lines.

The invention is also characterized and featured by a design, arrangement and construction of solid carbon dioxide press apparatus that is mechanically simple andeiiicient in operation, and is capable of construction and installation at relatively low cost.

With the fore'going'general objects, features and results in view, as well as certain others that will appear and be readily recognized from the certain novel features in construction and in combination of parts and elements of the apparatus, all as will be more fully and particularly referred to and specified hereinafter.

Referring to the accompanying drawings in which similar reference characters refer to corresponding parts and elements throughout the several figures:

Fig. 1 is a view, more'or less diagrammatic, of

a press apparatus of the invention'in vertical section, and showing the fluid pressure pump in elevation and the operating control unit in plan together with the arrangement of fluid pressure line coupling the pump, control unit, and press, the apparatus being shown in its starting position preparatory to commencing a block forming cycle.

Fig. 1A is a view in front elevation of the control unit and showing the control dial and operating control lever in position thereon corresponding to the starting position of the apparatus as shown in Fig. 1. p

Fig. 2 is a view of the press apparatus of Fig. 1, with the fluid pressure pump and control unit removed, and showing the press cylinder in raised position to receive a measured charge of snow from the charge measuring or intermediate snow chamber thereabove.

Fig. 3 is a view similar to Fig. 2, but showing the position of the press apparatus with the measured charge of snow transferred into the block pressing chamber of the raised press cylinder.

Fig. 4 is a view of the press apparatus at the completion of the block compressing step with the press plunger in raised compressing position and the formed block in the upper end of the press cylinder.

Fig. 5 is a view similar to the preceding views, but with the apparatus in position upon completion of a block and the press cylinder and press plunger lowered to remove the block from the press cylinder and support the block on the press plunger in position for removal from the apparatus.

Fig. 6 is, a viewin vertical section through a modified form of press apparatus of the invention, with the press cylinder and plunger in position for compressing a charge of carbon dioxide snow into a block. I

Fig. 7 is a view similar to Fig. 6, but showing the apparatus "at the completion of the block pressing with the formed block in position in the upper end of the press cylinder.

Fig. 8 is a view showing the press cylinder and plunger lowered and the completed block in position for removal.

Fig. 9 is a view, more or less diagrammatic, in cross section through the valve -control unit of Fig. 1, when in the 0 or neutral, inactive control position, and showing the fluid pressure pump partly in section with the fluid pressure lines connecting the pump with the valve control unit.

A preferred mechanical expression of a solid carbon dioxide press apparatus is disclosed in- Figs. 1 to 5 of the accompanying drawings, as an exempliflcation of the principles and features of my invention, and not in all respects as a limitation. The invention basically recognizes and contemplates that the principles and features thereof may be carried out in various other mechanicaland structural embodiments than those of the particular examples hereof. In the illustrated .following explanation, the invention consists indioxide snow above a snow press unit that is moved upwardly to the snow source to receive a. charge of snow and for compressing such charge of snow into a block, and which press unit, after block compression, is moved downwardly to permit of the block being discharged therefrom through the open upper end of the press unit by relative movement between the press and its compressing plunger.

In a preferred form of carbon dioxide press apparatus illustrated in Figs. 1 to 5 of the accompanying drawings as embodying the principles and features of the invention, a suitable base or cylinder ll surrounding the inner cylinder I0 and of annular form. A piston I2 is slidably reciprocally mounted in and. forms a sealing flt with the inner cylinder l0 and has the piston rod l4 extending upwardly through the cylinder and a distance thereabove. Within the outer annular cylinder ll, an annular or ring piston I5 is slidably mounted to form a sealing flt with the walls of the annular cylinder for vertical reciprocation therein, and this piston I5 is provided with an upwardly extended sleeve l6 slidably fitted around the outer wall of inner cylinder ill. A closure ring ila, or the like, is mounted over and closing the upper end of cylinder I I, around and forming a sliding and sealing flt with the outer side wall fixed the lower ends of suitable pressure rods or supporting posts l8 that extend vertically upward from flange II at suitable spaced points therearound. There may be two of such posts at diametrically spaced points on the flange, or any desired number of such posts suitably spaced around the flange may be employed. These support posts extend upwardly from the flange I1 and support on their upper ends the snow pressing and block forming cylinder 20 of the press unit, which cylinder provides the pressing chamber P therewithin of a round, rectangular-or any other desired or expedient shape in cross section.

The press cylinder 20 is provided with thelaterally or radially disposed lugs 20a extended outwardly therefrom a distance above the lwer end of the cylinder, there being one lug for each post l8, and these lugs receive. and are supported upon the upper ends of the posts I8, respectively, to mount and support press cylinder 20 in vertically disposed position therebetween. axially alined with pressure cylinder l0 and its piston rod M. The upper end of press cylinder chamber P is open, While the lower end thereof is closed by a suitable head 2| through which the piston rod l4 slidably extends in an axial bore through the head. Piston rod l4 extends upwardly a distancethroughthe press chamber P and is provided at its upper end within chamber P with the snow compressing head or plunger 22; The plunger 22 slidably fits in and is received by chamber P for yertical reciprocation,

but, in the example hereof, without forming a 75 per face sealing or gas-tight engagement with the chamber walls- The press cylinder 20 is thus mounted and carried by the piston sleeve l6 for raising and lowering by and with piston in cylinder ll, independently of and relative to the compressing head or plunger 22 in the press chamber P, while the plunger 22 is vertically reciprocal in. chamber P independently of press cylinder 20, by vertical reciprocation of piston I2 in the pressure cylinder ID. The relative arrangement pf the several elements is such that,"with pistons l2 and 15 in fully lowered positions, the press cylinder and plunger 22 are lowered and the operating or upof the plunger 22 .is disposed a slight distance above the upper end or edge of the cylinder 20, as clearly shown by Figs. 1 and 5 of the drawings.

The piston rod H has a collar or flange Ha therearound between the lower end of cylinder 20 and the flange structure l1 carried by piston sleeve Hi; This collar is so positioned on the pis-' ton rod l4 relative to the lower end or head 2| of cylinder 20, that upon downward movement or lowering of cylinder 20 from raised position, with the piston I2 and rod ll in raised position (see Fig. 4), the cylinder will engage collar Ma and force the piston rod and plunger 22 with piston l2, to lowered position. The purpose of such arrangement will be more fully explained hereinafter.

A source of carbon dioxide snow is provided mounted and supported in elevated position spaced above the press unit of the apparatus, in

.' which carbon dioxide snow may be continuously produced during block pressing operations, and from which measured charges of snow are fed or delivered to press cylinder chamber P for block formation therefrom. For instance, in the example hereof, a vertically disposed tubular casingor member is supported above the press unit in axial alinement with press cylinder 20 and provides chambers within which snow production is carried on during press operation.

The snow chamber forming casing 25 is mounted and supported in tire upper end of a vertically disposed casing section 26 which in turn is supported in spaced position above but in axial alinement with the press cylinder 20, by the vertically disposed supporting legs or columns 21 mounted at their lower ends on the laterally disposed arms 21a at the upper end portion of the pressure cylinder ll of the press apparatus. The casing section 26 is in axial alinement with casing 25 thereabove and forms an intermediate or snow charge measuring chamber M for receiving snow from the snow chamber S.

The lower end of casing section 26 terminates in a horizontally disposed laterally extended housing structure 28 having the bore or passage 29 therethrough in axial alinement with casing section 26 and forming the discharge mouth for chamber M. The housing structure 26 forms the supporting base for the casings 25 and 26, with their associated structure, and is mounted and supported on the upper ends of the legs or columns 21. The passage or discharge mouth 29 in the housing structure 28 for chamber M is vertically axially alined with the press cylinder 2Q and has an internal diameter or cross sectional shape equal to and the same as the external diameter or cross sectional shape of the upper end portion of press cylinder 20, so as to fit over and receive the upper end of the press cylinder when the latter is in its raised snow charge receiving and block pressing position (see Figs. 2, 3 and 4) The upper end portion of the press cylinder 20 may have, as in the present "example, areduced external diameter to provide a stop shoulder 20b therearound for engaging and forming a substantially gas-tight seal with the lower edge of the wall 29a around and defining mouth 29, when cylinder 20 is raised to position fitted into the mouth or passage 29.

The formation of solid carbon dioxide crystals or snow in the chamber S may in accordance with any desired or suitable. process for forming solid carbon dioxide, but in the example hereof, snow is produced in the well known manner by. the expansion of liquid carbon dioxide through the expansion valve V and the discharge nozzle N extended into the upper end of chamber S through the upper end closure head or cap 30 of the casing 25. The valve V and nozzle N are supplied with liquid carbon dioxide at any desired temperature and pressure (above the triple point the liquid line L leading from a usual or suitable source of liquid carbon dioxide which may be any type of liquefying system or any type of liquid carbon dioxide storage apparatus, which liquefying and/or storage apparatus it is not here deemed necessary to illustrate. The expansion of the. liquid carbon dioxide into chamber 5 results in the conversion of the liquid to gaseous and to solid carbon dioxide, the latter in crystal or snow form. The snow thus produced collects in the chamber S while the carbon dioxide gas is continuously withdrawn from the chamber through the gas line G from the upper end of the chamber back to any suitable system of reliquefaction and/or storage and return by line L as liquid tor expansion into chamber S.

The lower end of the snow chamber S is closed and opened by a slide ,valve 3| which is slidably mounted in a guideway 32 formed in a housing structure 33 disposed horizontally and laterally at the upper and lower ends of the casings 26 and 25. respectively. The slide valve 3| is disposed transversely of casings 25 and'26 and in closed position shown in Fig. 1, closes the lower end of chamber S and shuts the same oil? from communication with or discharge of snow therefrom to. the lower, intermediate or charge measurin chamber M. An opening or port 34 is formed vertically through slide valve 3| for registry with and alinement between the upper end of chamber M and lower end of chamber S to place these chambers in communication and permit passage of carbon dioxide snow from chamber S downinto chamber M, when valve 3| is movedcarrying it over into the housing structure. Such beveled edge 34a tends to' force the snow within the port downwardly into chamber M as the valve moves through the, snow column to closed position.

A slide valve 35 ismounted between the lower end of chamber M and the snow discharge* passage or mouth 29, in a suitable slldeway 36 disposed transversely of chamber M in the housing structure 26. The slide valve 35 is provided with be carried out I of carbon dioxide) by an opening or port '31 therethrough of the same diameter or cross sectional shape as the chamber M and for alinement and registry with the lower end of the chamber for discharge of snow therefrom through mouth 29, when the valve is slid to chamber opening position. The valve 35' forms and provides the upper surface or head against which a snow charge in cylinder is compressed into block form by press plunger 22 (see Figs. 2 and, 4).

The slide valves 3| and controlling the movement of snow through chambers S and M, are actuated by fluid pressure operating in cylinders and pistons operatively coupled with the valves.

The housing structure 28 for the slide valve 35 has a fluid pressure cylinder 38 supported in horizontal position spaced from one side of the structure in longitudinal alinement with valve 35 by the tie rods 38a. The piston 38b of cylinder 38 is'connected with the adjacent end of valve 35 by the piston rod 380 which extends through suitable packing glands into the valve slideway 36 where it is coupled to the valve.

Similarly, a cylinder 39 is supported in horizontally disposed position spaced from one side of the housing structure'33 for the slide valve 3| and in longitudinal alinement-with the valve, by the rods 39a. The fluid pressure actuated piston 39b in cylinder 39 is operatively coupled with the adjacent end of valve 3|, by the piston rod 390 extending through a suitable packing gland into the housing structure 33.

Fluid pressure for actuating the slide valve operating pistons 38b and 39b to open and close the valves, and for operating the press pistons l2 and I5, may be provided from any suitable source, but in the example hereof, I have more or less diagrammatically illustrated in Figs. 1

and 9 of the drawings, a pump unit H for developing hydraulic pressure for this purpose. This pump unit may, as in the present example, be of the two-stage 'or two plunger type, although the invention is not so limited, so that fluid is delivered by the pump at two pressures, that is, a low pressure and a high pressure; the low pressure for operating the slide valves 3| and 35, and the press raising ring piston l5, and the high pressure for actuating the press plunger piston I2. Included in the pump unit H is the air receiver 40 for the low pressure fluid, and the drain or collector 4| through which the pressure fluid is returned to the pump. If desired, or found expedient, any suitable means may be provided for heating the pressure fluid, such as a suitable heating coil (not shown) for the purpose of maintaining the desired temperature of the pressure fluid. The pump unit H is connected with the several pressure cylinders of the press apparatus by suitable pressure lines, through avalve control unit U that provides for control of the apparatus in accordance with a feature of the invention and in a manner hereinafter referred to and explained.

The fluid pressure lines from pump unit H and control unit U, include the low pressure fluid line 15 from air receiver 4|] to the control unit U, and

-the higl'. pressure fluid line 18 from the pump to connected with the control unit U by the fluid pressure lines and 46 communicating with opposite ends of the cylinder at opposite sides of piston 38b, respectively, while the cylinder 33 controlling slide valve 35' is connected with the control unit U by the fluid pressure lines 41 and 48 in communication with the cylinder at opposite sides of the piston 3911 within the cylinder 39.

In accordance with a feature of my invention 1 the control unit U is provided as a medium by which the operation of the press apparatus can be controlled by a single operator from one control point through the entire and complete block forming cycle, so that the operation of the apparatus from the control point is in effect automatic. In carrying out this feature the control unit U is provided with a single band control lever 50 for the operator, referring particularly to Figs. 1 and 9 of the drawings, and this lever and the unit are so designed and arranged that one revolution of the lever causes the press apparatus to complete a block pressing operation and produce a block of solid carbon dioxide in condition forremoval from the apparatus. As in the illustrated apparatus, there are eleven steps or operations of the apparatus to compress and form each block of solid carbon dioxide, the control unit, referring more particularly to Fig. 1A of the drawings, is provided with a control dial 5| having eleven stops spaced and consecutively numbered therearound from a neutral stop, and preferably so arranged as to each engage a portion of the operating lever, as the lever is swung therepast around the dial 5| (see'Fig. 9).

The control unit U in the particular example hereof, as more or less diagrammatically shown in Fig. 9 of the drawings, includes the valve unit body or casing 80 that provides a space or chamber longitudinally thereof through which the cam shaft 8| extends. The cam shaft 8| is journaled'in suitable bearings for rotation at the opposite ends thereof in the end walls of casing 80.

and the fluid line 15 is coupled into and discharges low pressure fluid from the pump pressure vessel 40 into this manifold. The unit is also provided with a common passage or manifold M5 for the return of fluid on which the pressure has been released down to substantially atmospheric, from the control unit to the return fluid line 11, and back to the fluid collector or tank 4|; This fluid tank or collector 4| forms the common source from which the low pressure and high pressure stages or sections of the pump unit H draw fluid through the lines 82 and 83, respectively, as will be clear by reference to Fig. 9. Thus, low pressure fluid is supplied through the line 15 to the common low pressure fluid passage or manifold N4 of the unit, and fluid is returned from the common atmospheric pressure manifold I I5 back to the pump collector 4| through the line 11. 1

The loW pressure fluid line 43 receives low pressure fluid directly from the manifold H4 and carries such low pressure fluid to the space in the cylinder above the ring piston |5. Each of the fluid pressure supply lines 42, 48, 46, 45 and 44 leads from the valve control unit to their respective parts of the solidification and pressing appa- This cam shaft 8| is disposed centrally or axially of the dial plate 5| and has the operating ratus, and each is controlled within the unit by inlet and outlet valves which are set in the desired positions by operation of the cam shaft 8I.

For instance, fluid pressure line 42 is connected in the unit into a fluid passage 4211 which communicates at one end with valve chamber "mm which there is mounted an inlet valve I I-2 for controlling flow through the chamber to the passage 42a. The opposite end of the passage 42a discharges into a valve chamber 420 in which an outlet valve III is mounted to control flow of fluid through this chamber. The chamber 421) receives low pressure fluid at one side of the valve I I2 from the manifold I I4; through the passage 42d. The chamber 420 at the opposite side of an outlet valve'I II from passage 42a, is placed in communication with a return fluid manifold H5 by the passage 426. Thus, with valve III closed and valve I I2 open, low pressure fluid flows into the fluid line 42. With inlet valve I I2 closed and outlet valve III open, fluid from the line 42 flows back under relieved pressure into the fluid manifold H5. I

The fluid pressure line 48 connects into a fluid passage 48a which communicates at one end with valve chamber 48b, in which there is mounted the inlet-valve" I I0, for controlling flow through the chamber to the passage 48a. The opposite end .of

passage 48a discharges into a valve chamber 480 in which there is mounted the outlet valve I09 for controlling flow of fluid through thischarm' her. The chamber 48b receives low pressure at one side of 'valve H0 from the manifold H4, through the passage 48d. The chamber 480 at the opposite side of the outlet valve I09 fromv passage 48a, is in'communication with the return fluid'manifcld H5 by the passage 486.

The fluid pressure line 41 is connected into the fluid passage 41a, which passage opens at one end into the valve chamber 411), in which chamber there is mounted an inlet valve I08 for controlling flow through the chamber to the passage 41a. The opposite end of passage 41a discharges into a valve chamber 410 in which the outlet valve I01 is mounted to control flow of fluid through this chamber; The chamber 41b receives low pressure fluid at one side of the valve I08 from the manifold II4 through the passage 41d. The

chamber 41c at the opposite side of the outlet- 4Ia discharges into the H5, through the pasvalve I01 from passage return fluid manifold sage 41c.

The low pressure fluid line 46 is connected with a fluid passage 46a which communicates at one end with valve chamber 461: in which there is mounted the inlet valve I06, controlling flow through the chamber to the passage 46a. -The opposite end of the passage 46a discharges into a valve chamber 460 in which the outlet valve I05 is mounted to control flow through this chamber. Thechamber 461) receives low pressure fluid at one side of the valve I06 from the manifold- II4, through the passage 40d. The chamber 460 at the opposite side of the outlet valve I05 from passage 46a discharges into the rear fluid manifold H5, by the passage 46c.

The low pressure fluid line is connected with a fluid passage 45awhich communicates at one end with valve chamber 451) in which there 'is mounted the inlet valve I04 controlling flow through the chamber to the passage 45a. The opposite end of the passage 45a discharges into a valve chamber 450 in which the outlet valve I03 is mounted to control flow of fluid through this chamber. The chamber 45?) receives low pressure fluid at one side of'the valve I04, from the manifold II4, through the passage 45d. The chamber 450 at the opposite side of the outlet valve I03, from passage 45a, is placed in communication with the return fluid manifold I I5 by the passage 45c.

The high pressurefluid line 44 connects into the passage 44a and this passage at one end connects with the inlet valve chamber 44b in which there is mounted the inlet valve IOI controlling flow through this chamber. The opposite end of passage 44a discharges into the outlet valve chamber 440 in which there is mounted the outlet valve I02 controlling flow through this chamber. The outlet chamber 440 at the opposite side of valve I02 from the inlet from passage 44a is placed in communication with the return fluid manifold H5, through the passage 44d. The inlet valve chamber 441) at the opposite sideof t4he inlet valve IOI .from the inlet to the passage 4a, pressure fluid line 16 through the passage Me. A circulating valve chamber I00a is provided in the valve unit adjacent valve chamber 44b and a circulating valve I00 is mounted in this chamber for controlling flow through the chamber. One end of this chamber I000. discharges into the fluid manifold II5 through the passage I00b, while the opposite end of this chamber at the other side of valve I00 is placed in communication with the high pressure fluid passage 44o by the branch passage I000. Thus, the high pressure fluid with valve I00 closed, valve IOI open,

' and valve I02 closed, flows into the high pressure closed and valve I02 line 44 and the fluid fluid line 44. With valve IOI open, pressure is relieved in is free to flow into the return fluid manifold I I5.

With inlet'valve IOI closed and the circulating valve I00 open, the high pressure fluid flows back into the rear fluid line through manifold H5, and is delivered without tank or collector M or the pump unit H.

The arrangement of the valves I00 to H2 inelusive, in the valve control unit is such that these valves are spaced apart in groups longitudinally along the unit. Each is of the reciprocating type with its operating stem extending into the chamber in which the cam shaft BI is mounted and each is provided within this chamber with a roller or other anti-friction member 83, which engages a cam 04 on the cam shaft 0|. By rotation of shaft 8|, through the operating lever 50, into the consecutive positions indicated by the dial 5I, these cams 84 reciprocate their respective valves to the desired positions controlling the fluid pressure system for the operation of the apparatus intended at such dial positions. Each valve is also controlled by a spring 85 which cooperates with and maintains the valves normally in closed positions on their respective seats with the various cams 84 operating to force the valves to open position against these springs and to permit the valves to return to normal position under, the action of the springs.

The various fluid pressure lines hereinb'efore identified that connect the control unit U with is placed in communication with the high pressure back to the fluid the pressure cylinders or press apparatus, are

or cycle referring now to Figs. 1, 1A and 9, of the drawings, the piston I2 and press plunger 22 tov gether with piston I5 and the press cylinder 20 are all in their lowered positions while the slide valves 3| and 35 are in their chamber closing positions with their operating pistons .391) and 3817 at the outer ends of cylinders 39 and 38. With the elements of the apparatus in such positions, the unitary operating control lever 50 is in a neutral position, vertically upwardly disposed at the dial stop marked 0 in the example hereof, (see Fig. 1A) and the valves of the control unit are set by the cams 84 so that the pump unit H, which is running continuously, merely returns the pressure fluid back to the fluid collector M of the pump unit. With the control unit in this neutral or inactive position, the cams 84 on the cam shaft 8|, hold or maintain all of the valves I03 to H2, inclusive, of the control unit, open, whercby low pressure fluid circulates from the pump unit through the low pressure lines [5, manifold I I4, through the open inlet and outlet valves and into the return manifold ||5, from whence this fluid is returned by the line 11 back to the collector 4| of the pump unit H. At the same time, the proper cams 84 operating the high pressure valves I00, IN and |02, have set these valves so that the circulating valve |00 is open, while valves I0| and I02 are closed, so that the high pressure fluid flows by line 16, passages 44e'and I000, then past valve I00 through the passage |00b and back to the pump collector 4| through the line 11.

With a valve control unit in the inactive or 0 position of the control lever, there is thus merely a constant circulation of the high pressure and low pressure fluid through the control unit and back to the pump unit. Liquid carbon dioxide'can now be expanded in the snow chamber S through valve V and nozzle N, and the snow thereby produced is collected in the chamber which is closed at its lower discharge end by the slide valve 3|, while the carbon dioxide gas is continuously drawn off through pipe line G and returned into the liquefying cycle or to a point of gas storage.

The press apparatus is now in position to start a block compressing cycle, and the operator moves the control lever 50 to the right around the dial 5| to the stop point numbered "1, thereon. In such position of the control lever 50, referring to Fig. 9, the inlet valve 2 is left open and outlet valves I03 to II are closed, so that the low pressure fluid passes from the manifold H4 and being unable to pass valves I09, I01, I05 and/or I03 to the return manifold ||5, builds up low pressure in the manifold '|I4 which in turn passes through passage 42d, past open valve 2, through pressure line 42, and into the space in cylinder I| below ring piston I5. As the pressure line 43 from the control unit to the space above ring piston I5 is in constant communica-' pressure exerted on the under surface of the-..

piston is approximately twice that exerted on the upper surface of the piston, and the piston |5 with its sleeve I6 is forced upwardly in cylinder l to raise the press cylinder 20 into position with its open upper end received in the snow discharge opening 29 there-above, as shown in Fig. 2 of the drawings, and with the press chamber P alined with chamber M closed therefrom by the slide valve 35. During this raising of the press cylinder ,20 to snow receiving and block compressing position, the piston |2 and press plunger 22 remain in lowered position with the plunger 22 then positioned at the lower end of press cylinder chamber P. This position of the press cylinder 20 and press plunger 22 is clearly shown by'Fig. 2 of the drawings.

During the further operation of the apparatus and until completion of the block pressing operation, the control unit maintains the low pressure fluid in cylinder below piston I5 to maintain the piston and press cylinder 20 in their raised positions, of Figs. 2, 3 and 4.

After the raising of cylinder 20 by fluid pressure in cylinder H, the operator swings the control operating lever 50 downwardly to the dial stop marked 2 (see Fig. 1A) which causes the proper cam 84 to open the inlet valve 0, outlet valve |09 remaining closed. The opening of valve I I0 causes low pressure fluid to flow through fluid line 48 into cylinder 39 at the outer side of piston 39b. The operator then continues swinging the control lever 50 until the dial stop "3 is reached, at which stop the cam 84 for the valve I0! is positioned to cause this valve to open. The

cam for valve I08 maintains that valve closed, whereupon the line 41, from cylinder 39 at the opposite side of the piston 39b is opened to the return fluid manifold 5, thus relieving pressure at that side of piston 39b so that the positive pressure fluid from line 48 forces piston 39b inwardly through cylinder 39 and slide valve 3| is slid to position with the valve port 34 alined with and opening the lower discharge end of chamber 5, as shown in Fig. 2 of the drawings. When the slide valve 3| is in this opened position, the carbon dioxide snow collected in chamber S passes by gravity from chamber S through valve port 34, into and fills the intermediate or measuring chamber M with a charge of snow which then rests therein, on the slide valve 35 at and closing the lower discharge end of the chamber M.

Following the filling of chamber M with a charge of the carbon dioxide snow, the operator then swings control lever 50 downwardly from stop 3 to stop "4 on the control dial 5|. At stop "4, the cams 84 for the valves I01 and I08 actuate these valves to close I01 and to open I08 for flow of low pressure fluid from the manifold H4 through the fluid line 41 and into the cylinder 39 at the inner side of the inwardly moved slide valve piston 39b. Then, by further swinging of the control lever 50, to the dial stop position "5 the cams 84 for valves I09 and II 0, respectively, actuate these valves to close valve II 0 and open valve I09. .Thus, fluid line 48 is closed off from the low pressure fluid and is opened to the return fluid manifold I l5 which results in relief of pressure at the outer side of piston 39b, and the return flow of the fluid therein at substantially atmospheric pressure back into the manifold and through line 1'! to the pump colfor transfer into the press chamber P or the press cylinder 20.

Frpm dial stop position "5 and after the closing of the slide valve 3I, the operator swings lever 50 to the dial stop 6 which causes the cams 84 for the valves I05 and I06'to open valve I06, valve I05 remaining closed, so that low presresults in piston 38b being forced inwardly and moving slide valve to the positions shown in Fig. 3, with the valve port 36 alined with and opening the lower end of chamber M. The measured charge of snow in chamber M then moves downwardly by gravity through valve port 36 into the press chamber P of press cylinder 20. By the use of the chamber M to measure off a quantity of snow for filling the press chamber, there is insured substantially the same weight of snow for each charge of the press chamber, and the solid carbondioxide blocks pressed from such snow charge will therefore be of substantially uniform weight.

swung right on past stop With the measured snow charge transferred from chamber M into press chamber P as shown in Fig. 3 of the drawings, the operating lever 50 is then swung to stop 8 position on dial 5I which causes the cam of valve I03 to close this valve while the cam for valve I04 opens that valve, so that the fluid line is connected with the low pressure fluid manifold I I4 and low pressure fluid flows into the cylinder 30 at the inner side of piston 38!). The control lever is then 8 to stop 9 position, which actuates the cams for valves I05 and I06, to open valve I05 and to close I06, so that fluid line 46 is placed in communication through outlet valve I05 with the return fluid manifold II5. Pressure is thus relieved in cylinder 30 at the outer side of piston 38!) and the fluid therein is permitted to flow back to the pump collector M at substantially atmospheric pressure. Thereupon piston 38!) is forced outwardly in cylinder 38 and the slide valve 35 is drawn thereby to the position of Fig. 4 closing the lower end of chamber M andacross and closing the upper end of the press cylinder chamber P to form in effect the press head against which the snow charge is pressed into block form. The press chamber P is in this manner charged with snow and then closed in preparation for the block pressing operation.

To carry out the pressing of the snow charge into a block in the press chamber P of press cyl-. inder 20, the operator. swings the control lever 50 to the stop position 10 on'the dial 5| and in such control position the rotation of the cam shaft 8| causes the cams 84 for the valves I 00, IN and I02 to close-circulating valve I00 to open inlet valve IM and outlet valve I02 remaining closed. With the valves so set, high pressure fluid from the line I6 flows past valve IOI through passage 44a into the high pressure fluid line 44 which discharges the high pressure fluid into the press cylinder I0 below the piston i2 therein.

The high pressure fluid from line 44 forces piston I2 upwardly, and through piston rod I4 forces the press'plunger 22 upwardly in press cylinder 20 to compress the charge of snow in press chamber P between the plunger 22 and the press head forming valve 35 into a homogeneous block I of solid carbon-dioxide of the required density. In Fig. 4 of the drawings, the press plunger is shown at the conclusion of its pressing stroke and with the completed block I in the upper end of the press cylinder 20 between plunger 22 and the valve 35 across and closing the upper end of the press cylinder to provide the press head during the pressing operation.

During the pressing of the carbon dioxide" snow in the press cylinder 20 by the upward stroke of the plunger 22 there will be some carbon dioxide gas from the snow passing downwardly'past the plunger into the lower portion of the press cylinder chamber P, and to remove this gas and prevent its loss, gas ofitake line is provided from the lower end of press chamber P. The line 55 may preferably lead the gas back to any gas storage system or means of liquefaction for subsequent return to the system and to the liqui 'line L. For example, if desired, the gas line 55 can discharge into the main gas ofitake line G from the snow forming chamber S of the press apparatus.

Similarly, a gasofitake line 55a can be provided from the intermediate or snow measuring chamber M in order to carry off any carbon dioxide gas formed in such chamber. The line 55a may, as in the case of ofltake line 55, lead to main gas oiftake line G, or to any gas storage or means of liquefaction for return in liquid form to line L.

Upon completion of the pressing operation and the formation of a snow charge in press chamber P into the block or cake I of dense solid carbon dioxide as shown in Fig. 4, the control lever 50 is swung to the stop position 11 on thecontrol dial 5|. In this position of the control lever the cams 84 for the valves III and H2, actuate these valves to open valve III and close the pressure fluid inlet valve 2'. At the same time, the cams for high pressure fluid valves IN and I02 operate these.valves to close valve IM and to open valve I02. Thus, the fluid pressure is relieved beneath pistons I2 and I5, by opening the spaces in the cylinders II and I0, beneath these pistons, to the fluid return manifold II5 to permit the fluid from these cylinders to flow back through the line II at substantially atmospheric pressureto the collector M of the pump unit H. The low pressure fluid passing through the line 43 into ring cylinder II above ring piston I5, forces the piston I5 downwardly and lowers press cylinder 20 fromits raised position. The press plunger 22 and piston I2, may move downwardly under their own weight and by the positive downward movement of the piston I5 and press cylinder 20.

The press cylinder 20may move downwardly relative to plunger 22 and from the block I on the plunger to remove this block from the cylinder into exposed position. This downward movement of the cylinder past plunger 22 and block I can continue until the lower end head 2| of cylinder 22 engages collar I4a on piston rod I4, whereupon the piston rod is moved downwa dly with cylinder 20 to move plunger 22 and piston I2 to their lowered position of Fig. 5. In lowered position, the carbon dioxide block I is comremoved. from press cylinder 22 and can then be easily and quickly removed as a completed block from the apparatus.

After completion of the press unit lowering and the discharge and removal of the formed block I of solid carbon dioxide, the apparatus is ready for another block forming cycle of operations. The control lever is swung up from stop 11 to its neutral position opening valves I00, I03, I06, I0I,'IIO and H2, closing'valve I02 whilst valves I04, I05, I08, I09 and I II remain open and valve IOI remains closed. Thus the various valves of the unit are caused to assume positions hereinbefore referred to in which the low pressure fluid flows through the open valves to return manifold H5, while the high pressure fluid flows through the open circulating valve I00 to the return manifold I I5, the high pressure inlet valve Illl being then closed. In this manner the control unit and its associated apparatus is in inactive position and the pump unit merely continuously circulates the high and low pressure fluid through the unit and back through the return line 11 to the collector tank 4|.

Also, it will be realized that the operation of the control unit is not limited to eleven stop or operating positions and that by making the movements of each valve individually or by making more movements simultaneously, the number of positions may be increased or decreased.

In order to prevent or reduce the possibility of freezing the pressure fluid in the various fluid pressure actuated cylinders of the apparatus, due' to the extremely low (110 F.) temperature encountered with the solidification of the liquid carbon dioxide and of the snow produced the apparatus of the invention is designed to reduce heat transfer from the pressure fluid to the carbon dioxide to a minimum. For example, by separating or spacing the carbon dioxide snow receiving press cylinder 20 from the fluid pressure cylinder II .and piston I5I6, and connectingt-hese elements by the rods or posts I8, a minimum path for heat conduction is afforded from the fluid in cylinder II to the carbon dioxide in press cylinder 20. Similarly," the slide valve operating cylinders 38 and 39 are separated or spaced from the housing structures 33 and 28, and connected thereto and supported therefrom by the rods 38a and 39a, respectively, which provide a minimum of heat conducting path from the pressurefluid in these cylinders. As a further safeguard, where necessary, the pressure fluid may be heated by a heating coil as hereinbefore referred to, in the pump unit H.

The arrangement of the intermediate or snow measuring chamber M and the slide valves 3| and 35 in their operating relation with snow production chamber S and the press unit cylinder 20, is such that continuous production of snow ,in chamber M is carried onduring block forming operations of the apparatus and without interruptions in snow production during block compressing by press plunger 22. I Thus continuous snow production is made particularly efl'icient due to the fact that either one or both of slide valves 3| and 35 are in position shutting off the snow production chamber S at all times during operation of the press apparatus.

The use of the snow charge measuring chamber M, as hereinbefore pointed out, provides for uniformity in the weight of the snow charges fed to the press chamber and results in the production of blocks of uniform weight, a highly desirable result for mechanical press production of solid carbon dioxide blocks. The block discharging by the lowering press cylinder 2 0 in relation to press plunger 22, is positive in operation and avoids the difiiculties of the prior non-positive block discharge types of apparatus. By lowering the press cylinder past the plunger 22 to the discharging position of Fig. 5, the block I is completely removed from the press cylinder and is positioned resting exposed on plunger 22 for free and unobstructed removal laterally from the press apparatus. The foregoing characteristics of and results from the press apparatus contribute especially to the increased speed of production possible, while the unitary control insures a substantially automatic and foolproof operation by a single and unskilled operator.

A modified form of pressing apparatus embodying certain of the basic features of the invention is illustrated, more or less diagrammatically in Figs. 6, '7 and 8 of the drawings, and in such modified form the intermediate or snow charge measuring chamber of the preferred form of the apparatus is eliminated. Referring to Figs. 6 to 8, the apparatus includes a base B with the concentric inner and outer pressure cylinders- I0' and II' having the pressure actuated pistons I2 and I5, respectively, slidably mounted therein.

The press cylinder 20' is in this example, directly carried on and as an upward continuation of the upwardly extending sleeve I6 of piston I5 and is closed at its lower open end by the press plunger 22.

A head or housing structure 60 is supported spaced above the press unit by the columns 21' and includes a passage or vertical chamber 6I therethrough in vertical alinement with press cylinder 20'. Thus chamber 6| terminates at its lower end in the enlarged discharge mouth portion 29 for receiving the upper end of cylinder 20 when the latter is in raised position. A vertically disposed tubular casing is mounted on structure 60 in the upper end of chamber GI extending upwardly therefrom to provide the,

snow forming chamber S. A snow nozzle N and liquid expansion valve V in the carbon dioxide liquid line L, together with a gas off-take line G are provided for snow production in chamber S, in an identical manner as that described in connection with the form of the apparatus of Figs. 1 to 5' hereof.

The housing structure 60 provides a slideway I52 therein across the passage or chamber 6|, and a slide valve 63 is mounted therein having the vertical port or opening 64 therethrough of a diameter or cross section equal to the diameter or cross-section of passage or chamber GI. The valve 63 is actuated by a fluid pressure cylinder 65 and piston 66 therein connected with the valve by a piston rod 61; the cylinder being mounted on the structure 60 at one end of valve slideway 62. The valve 63 is shown in open position with the port 64 thereof alined with chamber or passage 6| for passage of snow from chamber S into press cylinder 20', in Fig. 6, while in Figs. 7 and 8 the valve is shown in closed position. The pressure fluid passages to and from cylinder 65 at opposite sides of piston 68 are shown at 6511 and 65b. j

The pressure cylinder I0 is provided with the pressure fluid passages 68 and 69 in communication therewith at opposite sides of piston I 2 and the cylinder II is provided with the pressure fluid passages I0 and II thereinto at opposite sides of its piston I5. The cylinders I0, II and 65 are conected by suitable pressure fluid lines closing the lower 'ders and their pistonsis .such cylinder.

iorced. upwardly by of pressure fluid, such as the pump 1, and the actuation of these cylincontrolled through suitable valve means, such as provided by a control unit of the type of unit Uof .Fig. 1, if desired.

In the operation and use of the form of press apparatus ofiFigs. 6 to 8, and press plunger 22' are in the lowered positions of Fig. 8 st the start of a solid carbon dioxide block forming cycle of operations. The press cylinder/ 20 is then raised to the position of Fig. 6, the plunger 22' remaining in lowered position end of the cylinder by admission of press fluid beneath piston IS in cylinder Ii. The slide valve 63 is then moved to open position and carbon dioxide snow formed in chamber S hen moves downwardly into and fills the press cylinder 20', as shown in Fig. 6 of the. drawings.

The slide valve 63 is then moved back to closed position cutting oif chambers S and 6| from the press cylinder 20' and closing the upper end of The press plunger 22' is then fluid pressure admitted into cylinder l below pistonl2', and the snow in the with a source unit H of Fig.

press cylinder is compressed into a dense homogeneous block of solid carbon dioxide, by Fig. 7 of the drawings.

After completion of the block, the press cylinder 20' and the press plunger 22' are both lowered into the positions of Fig. 8. As the press cylinder Zll'has a greater downward movement than plunger 22, the cylinder will movedownwardly past and relatively to the plunger, so that, in full lowered positions the upper end of the cylinder is located flush with or slightly below the upper face of plunger 22', as will be clear by reference to Fig. 8. Thus, the cylinder 20' is removed from'the block, which is then in a fully discharged position resting on plunger 22' and can be readily removed from the apparatus.

While the invention is primarily intended for the production of blocks or cakes of solid carbon dioxide, or so-called carbon dioxide ice,'an apparatus of the invention may be adapted for forming blocks from other solidified gases and various other materials where similar or equivalent conditions are encountered, or where the adas shown vantages andresults from an apparatus of they invention may be desirable. Also. while in the mechanical expressions of the examples of the invention here shown, the press is vertically moved toward and from pressing position at the snow source, the invention is not necessarily so limited.

Within the-broad scope of the invention the press may be mounted for horizontal movement toward and from the snow source, or at any angle between the horizontal and the vertical. The basic feature of and included in the invention resides broadly in the relative movement of the press and the source of snow with the press and source in association for pressing and in disassociation for completed block removal.

It is also evident that various changes; modifi-' cations, substitutions, additions and eliminations might be resorted to without departing from the spirit and broad scope of my invention, and hence I do not wish to limit myself in all respects to theexact and specific disclosures hereof.

What I claim, is:

1. Inpressing apparatus for compressing solidcarbon. dioxide into blocks, in combination, a structure providing a solid carbon dioxide receiving chamber having a lower side discharge opening therefrom, a pressing cylinder below said chamber forming. structure and mounted for the press cylinder 2|!" movement to and from raised position for receiving a charge of solid carbon dioxide from said chamber through the chamber discharge opening, a pressing plunger in said cylinder for pressin a charge of solid carbon dioxide into a block with the cylinder in raised position, and said pressing plunger ejecting the completed block during downward movement of the pressing cylinder from raised position.

2. In pressing apparatus for compressing solid carbon dioxide into blocks, a structure providing a solid carbon dioxide receiving chamber having a bottom discharge opening therefrom, aclosure member for opening and closing said discharge opening, a pressing cylinder below said chamber forming structure and mounted for movement to and from raised position receiving a charge of. solid carbon dioxide from said chamber when said closure member is opened, a pressing plunger in the press cylinder adapted after the press cylinder is raised and receives a charge from the chamber and said closure member is closed, to press the charge of said carbon dioxide into a block, and said press cylinder downwardly movable relative to the plunger after completion of the block to cause the plunger to eject the block from the cylinder.

3. In apparatus for pressing solid carbon dioxide into blocks, the combination with a source of solid carbon dioxide; of a press cylinder mounted for movement to and from position at said source in association therewith to receive a charge of solid carbon dioxide therefrom, a pressing plunger in said cylinder and movable therein with the cylinder in position at said source to press a charge of solid carbon dioxide in the cylinder into a block, and said cylinder upon completion of the solid carbon dioxide block therein movable from position at the source and relative to said plunger tocause the plunger to completely eject the completed block from the cylinder.

- 4. In apparatus for pressing solid carbon dioxide into blocks, in combination, a structure providing a chamber for collecting solid carbon dioxide therein and a measuring chamber for receiving a charge of solid carbon dioxide from said collecting chamber,a means for opening and clos-. ing communication between saidchambers, said measuring chamber having a discharge there- 'from and a closure member for opening and closing said discharge, a press cylinder mounted for movement toward and from position to receive a measured charge of solid carbon dioxide from said measuring chamber through chamber discharge, a pressing plunger in said cylinder movable to press a charge therein into a block of solid carbon dioxide when the cylinsaid der is in charge receiving position and said chamto completely eject a measuring chamber therebelow for receiving solid carbon dioxide from said supply chamber, means tor opening and closing communication between said chambers, said measuringchamber having a lower end discharge mouth and a closure member -for openingand closing said discharge mouth, a press cylinder below said measuringchamber and mounteTNn axial alinement therewith for movement upwarmpositicn tor receiving a charge of solid carbon dioxide when said closure member is opened, a pressing plunger in said cylinder for upward movement therein with the cylinder in raised charge receiving po-,

inder below said chamber, means for moving said pressing cylinder toward and from said chamber, said cylinder in raised position adapted to receive a charge of solid carbon dioxide from the chamber, a pressing plunger in said cylinder operable to compress the solid carbon dioxide in the cylinder into a block with the cylinder in raised position, and said cylinder and plunger movable downwardly from raised position after completion of the block pressing for removal of the completed block from the cylinder.

7. In apparatus for pressing solid carbon dioxide into block form, in combination, a structure providing a solid carbon dioxide receiving chamber having a discharge opening therefrom, a closure member for opening and closing said discharge opening, fluid pressure actuated means for operating said closure member, a pressing cylinder mounted for movement to and from position at said chamber forming structure for receiving a charge of solidcarbon dioxide therefrom through said discharge opening, fluid pressure actuated means for moving said cylinder to and from charge receiving position, a pressing plunger movable in said cylinder to press a charge of solid carbon dioxide therein to block form when the cylinder is in charge receiving position at said chamber discharge, fluid pressure actuated means for operating said pressing plunger, said pressing cylinder movable from charge receiving position relative to said plunger to cause the plunger to eject the completed block from the cylinder, a source of fluid pressure for said pressure actuated means, and a unit control for the .fluid pressure from said source to the pressure actuated means to cause operation of said means, to open and close said chamber discharge closure member and to move said pressing cylinder and plunger in the required sequence for a cylinder charging, block compressing, and block ejecting cycle 01' said apparatus.

8. The combination with apparatus for pressing solid carbon dioxide into blocks, including a source of solid carbon dioxide, fluid pressure actuated valve means controlling discharge of solid carbon dioxide from said source, a pressing cylinder movable to and from position associated in substantially gas-tight relation with and receiving solidcarbon dioxide from saidsource, a pressing plunger movable in said cylinder to and from position for pressing a charge of solid carbon dioxide in the cylinder into a block, andfluid pressure actuated means for independently moving said pressing cylinder and pressing plunger; of a source of fluid pressure for actuating said valve means, and said cylinder and plunger moving means, and a control unit interposed between said pressure source and the pressure actuated means for consecutively controlling the pressure actuated means to cause the required operation of the valve means, the pressing cylinder, and the pressing plungerto perform a block compressing cycle of the apparatus.

9. In apparatus for pressing solid carbon dioxide into block form, a vertically movable pressing cylinder having an open upper end for receiving a charge of solid carbon dioxide for pressing into a block in the cylinder, a structure spaced above the pressing cylinder and providing a head for closing the upper end of the cylinder and against which the charge in the cylinder is pressed ints block form, a plunger reciprocable in the cylinder for pressing a charge in the cylinder against said head, and means for raising said cylinder to position closed by said head forming structure and for lowering said cylinder after completion of a block of solid carbon dioxide therein to position for completed block removal with the cylinder in lowered position.

10. In apparatus for compressing solid carbon dioxide into blocks, a pressing cylinder having a normally open charging and discharging end, means normally spaced from the open end of said cylinder for closing said open end, said cylinder mounted for movement to and from position with its open end closed by said cylinder. closing means, and a plunger movable in saidcylinder to compress a charge of solid carbon dioxide into a block against said cylinder closing means with the cylinder in position closed by said means, said cylinder movable from position closed by said means forejectment of a completed block by said plunger.

11. In apparatus for pressing solid carbon dioxide into blocks, a vertically disposed fluid pressure cylinder having a fluid pressure actuated piston therein operatively connected with a platform structure at the top of the cylinder for raising and lowering by the piston, a source of pressure fluid connected with the cylinder for operating said piston therein, a vertically disposed solid carbon dioxide pressing cylinder spaced above said platform structure and supported therefrom by spaced rod members of relatively small cross sectional area to provide minimum heat conduction paths from the pressure fluid in the cylinder therebelow to the intensely cold solid carbon dioxide in the pressing cylinder.

12. In apparatus for pressing solid carbon dioxide into blocks, a pressing cylinder bodily movable axially to and from position in which a charge of solid carbon dioxide is pressed therein into a block at one end of the cylinder, means for moving the cylinder to and from pressing position, a pressing plunger in the cylinder normally positioned therein opposite the block pressing end of the cylinder and movable axially in the cylinder to and from the block pressing end thereof, means for forcing the plunger under pressure to the block pressing end of the cylinder when the latter is in pressing position to press a charge of solid. carbon dioxide into a block, said cylinder after completion of a block therein movable from pressing position relative to and independently of the plunger a distance to completely eject the block from the cylinder and formed to enga e the plunger upon continued movement to move the latter with the ejected block thereon to position for removal of the block from the plunger.

13. In apparatus for producing solid carbon dioxide and for pressing it into blocks, means for producing solid carbon dioxide, including a chamber for collecting the solid carbon dioxide therein, a carbon dioxide pressing unit below co cylinder movable from said collecting chamber, including a. press cylin der and a press plunger reciprocable therein, said press cylinder mounted for movement to and from position raised to said chamber for receiving a block forming charge of solid carbon dioxide therefrom, closure means operable to shut ofi communication between said chamber and cylinder after the latter is charged, said plunger movable upwardly in the cylinder to compress the charge therein with the cylinder in raised position, said closure means providing a head against which the solid carbon dioxide is pressed into a block by said plunger,and the cylinder movable downwardly from raised position after completion of a block for removal of the block therefrom.

14. In apparatus for pressing solid carbon dioxide in combination, a structure providing a solid carbon dioxide receiving chamber having a discharge opening therefrom, a closure member for opening and closing said discharge opening, fluid pressure actuated means for operating said closure member, a pressing cylinder mounted for movement to and from position at said chamber forming structure for receiving a charge of solid carbon dioxide therefrom through said discharge opening, fluid pressure actuated means for moving said cylinder to and from charge receiving position, a pressing plunger movable in said cylinder to press a charge of solid carbon dioxide therei n when the cylinder is in charge receiving position, fluid pressure actuated means for operating said pressing plunger, said pressing cylinder movable from charge receiving position relative to said plunger to cause the plunger to eject the block of pressed solid carbon dioxide from the cylinder, a source of low and high pressure fluid connected with said fluid pressure actuated means for supplying low pressure fluid to the closure operating means and the pressing cylinder moving means, and for supplying high pressure fluid to said pressing plunger I operating means.

, from,

, means for supplying, low

15. In apparatus for pressing solid carbon dioxide, a structure providing a solid carbon dioxide receiving chamber having a discharge opening therefrom, a closure member for opening and closing said discharge opening, fluid pressure actuated means for operating said closure member, a pressing cylinder movable to and from position at said chamber forming structure .for receiving a charge of solid carbon dioxide therefluid pressure actuated means for moving said pressing cylinder to and from charge receiving position,.a pressing plunger movable in said cylinder for pressing a charge of solid carbon dioxide therein when the'cylinder is in charge receiving position, fluid pressure actuated means for operating said pressing plunger, said pressing charge receiving position relative to said plunger to cause the plunger to eject the block of pressed carbon dioxide from the cylinder, a source of low and high pressure fluid connected with said pressure actuated pressure fluid to the closure operating 'means and the pressing cylinder moving means, and for supplying high pressure fluid to said pressing plunger operating means, and a unit control interposed between said fluid pressure source and the pressure actuated means for consecutively controlling the pressure actuated (means to cause the required in sequence operation or said closure member, press cylinder, and pressing plunger to form a pressfluid pressure, and a ing and pressed block ejecting cycle of the apparatus.

16. In apparatus for mechanically pressing solid carbon dioxide and the like, in combination, a container for solid carbon dioxide, a mechani-- cal press normally positioned spaced from said container, and said press mounted for movement between said normal position and position in substantially gas-tight association with said container for receiving a charge of solid carbon dioxide from the container. I

17. In apparatus for mechanically pressing solid carbon dioxide and the like into blocks, in combination, a supply container for the solid carbon dioxide, a mechanical pressfor receiving a charge of solid carbon dioxide for pressing, and said supply container and press mounted for relative movement between normal position spaced apart a distance for removal of a block from the press without displacement of press or container, and another position in substantial gas-tight association in which the. press receives a charge from said supply container.

18. In apparatus for mechanically pressing chamber for receiving acharge of solid carbon dioxide from the chamber.

19. In combination, afluid-operated pressing apparatus for pressing solidified carbon dioxide into blocks, fluid pressure operated means for controlling the charging of the pressing apparatus with solidified carbon dioxide, means for forming solidified carbon dioxide, a source of fluid pressure from the source to the pressing apparatus and the means for controlling said charging, said control unit having a single control operating member movable step? by step through a sequence of control positions to cause operation of the apparatus through a charging and block compressing cycle.

20. In apparatus for mechanically pressing solid carbon dioxide into blocks, a fluid pressure actuated mechanical press operable to press a charge of solid carbon dioxide into a block and eject the completed block, fluid pressure controlled means for controlling the charging of the press with solid carbon dioxide, a source of fluid pressure connected with the press and with said means for controlling said charging for operating the same through a charging and block compressing and ejecting cycle, and a fluid pressure control unit operable through a series of consecutive control positions to cause in sequence control unit for controlling solidified carbon dioxide therefrom, a pressing plunger in said cylinder movable therein with the cylinder in position at the source to pressa charge of solidified carbon-dioxide in the cylinder, said cylinder upon completion of the pressing of a charge of solidified carbon dioxide there-. in movable'from position at the source to a position for removal of the pressed charge from the cylinder, and means for moving said cylinder and pressing plunger.

22. In apparatus for pressing solidified carbon dioxide, in combination, a normally substantially gas-tight solidified carbon dioxide supply chamber, a measuring chamber in substantially gastight communication with said supply chamber for receiving and measuring solidified carbon dioxide therefrom, a closure for closing communioutlet and closure means for closing said outlet and substantially sealing the chamber, means for actuating said closure means, a mechanical press mounted for movement between normal position spaced from said measuring chamber and a position in substantially gas-tight communication with said chamber for receiving a measured charge therefrom when said measuring chamber discharge outlet closure means is opened, and means for moving said press.

24. In apparatus for compressing solid carbon dioxide and the like into blocks, a solid carbon dioxide supply chamber normally closed to the atmosphere'and having a normally closed discharge outlet, in combination with, a solid carbon dioxide compressing and block forming unit having a compressing and block forming chamber therein, said unit being normally positioned spaced from said supply chamber for removal of a completed block from the unit, and the said unit mounted for movement between said normal position and a position associated with the supply chamber, with the chamber of the unit in substantially gas-tight relation with the supply chamber discharge outlet for receiving a charge of solid carbon dioxide therein from the supply chamber.

25. In apparatus for pressing solidified carbon dioxide and the like into blocks, in combination, a substantially gas-tight solidified carbon dioxide supply chamber, a charge measuring chamber in substantially gas-tight communication with said supply chamber for receiving a charge of solidified carbon dioxide from the supply chamber, said measuring chamber having a discharge outlet' and closure means therefor, said closure means being operable to open said outlet and to close the same to substantially seal the chamber, and a pressing unit in gas-tight association with said measuring chamber outlet to receive a measured charge of solidified carbon dioxide from the chamber when said closure means is in open position. A

26. In apparatus for pressing solidified carbon dioxide and the like into blocks, in combination, a substantially gas-tight solidified carbon dioxide supply chamber, a charge forming chamber in substantially gas-tight conununication with said supply chamber for receiving solidified carbon dioxide from the supply chamber, said charge forming chamber having a discharge outlet and closure means for such outlet, said closure means ,to block form, said press being operable to open said outlet and to close thesame to substantially seal the chamber, and pressing means including a pressing chamber in gas-tight association with said charge-forming chamber outlet to receive a charge of solidified carbon dioxide 'i'rom the chamber when said closure means is in opened position, and the said closure means when in closed position providing a wall of the pressing chamber against which a charge is pressed to form a block of solidified carbon dioxide.

27. In apparatus for pressing solidified carbon dioxide and the like into blocks, in combination, a substantially gas-tight solidified carbon dioxide supply chamber normally closed to atmosphere, a charge forming chamber normally closed to atmosphere and in substantially gas-tight communication with said supply chamber, closure means between said supply and charge forming chambers for closing communication between and substantially sealing said chambers from each other and for opening communication. between the chambers for passage of solidified carbon dioxide from the supply chamber to the charge forming chamber, said charge forming chamber having a charge discharging outlet therefrom, closure means for said outlet operable to open the same and to close and substantially seal the same, and pressing means including a pressing chamber in substantial gas-tight association with said charge forming chamber outlet when the closure means therefor is in open position for transfer of a charge of solidified carbon dioxide to the pressing chamber, said closure means for thecharge forming chamber outlet providing a wall of the pressing chamber when in position closing the charge forming chamber from the pressing chamber.

28. In apparatus for mechanically pressing solid carbon dioxide and the like into blocks, in combination, a solid carbon dioxide supply chamber, a charge measuring chamber in substantially gas-tight communication with said supply chamber, said measuring chamber being adapted to receive solid carbon dioxide from the supply chamber and to form the same into a measured charge of predetermined quantity, and a pressing unit in gas-tight association with said measuring chamber for receiving a measured charge therefrom and for pressing such charge into a. block.

29. In apparatus for pressing solid carbon dioxide and the like into blocks, in combination, a solid carbon dioxide supply chamber, a measuring chamber for receiving and measuring a charge of solid carbon dioxide from said supply chamber, said measuring chamber being in gastight communication with the supply chamber and having a discharge outlet, closure means for said measuring chamber discharge outlet, and a pressing unit mounted for movement between normal positions spaced from said measuring chamber and positioned in gas-tight association with said chamber for receiving a measured charge therefrom when said chamber discharge closure means is opened. I

30. In apparatus for mechanically pressing solid carbon dioxide and the like into blocks, a fluid pressure actuated mechanical press for pressing a charge of solid carbon dioxide therein having a pressing chamber closed to atmosphere during a pressing operation, means controlled by fluid pressure for controlling the charging of carbon dioxide, said means the press with solid for controlling said opening therefrom,

and press charging means to cause an in sequence operation of the charging means and press for a complete block-forming cycle of the apparatus. 1 31. In apparatus forpressing solid carbon dioxide and the like into I blocks, in combination, a solid carbon dioxide chamberh'aving a discharge opening for sealing the chamber from atmosphere, and a, mechanical press mounted for movement between normal position spaced from said solid carbon dioxide-chamber and position at and in substantial gasstight communication with said chamber discharge opening for receiving a, charge from and pressing the same intoa block, said chamber discharge opening closure, when in closed position, providing the press head against which a charge is pressed by said press.

'32. In apparatus for pressing solidified carbon dioxide and the like, in combination, a normally substantially gas-tight solidified carbon dioxide supply chamber, ameasuring chamber in substantially gas-tight communication with said supply chamber for receiving and measuring solidified carbon dioxide therefrom, a closure for shutting off communication and forming a gas- -tight seal between said, supplyv chamber and said measuring chamber," and a mechanical press in gas-tight communication with said'measurinschamber to receive a measured charge of solidifled carbon dioxide therefrom forpressing into a block.

33. In apparatus for pressing solidified carbon dioxide and the like into blocks, in combination, a gas tight solidified carbon dioxide supply chamber normally closed to atmosphere, a charge forming chamber normally closed to atmosphere and in gas-tight communication with said supply chamber, closure means between said supply and charge forming chambers for closing communication between and sealing said chambers from each other and for opening communication between the chambers for passage of solidified cartherefrom, closure means for said outlet operable to open the same and to close and substantially seal the same, and pressing means including a pressing chamberin substantial gas-tight association with aid charge forming chamber outlet when the closure means therefor isin opened position for transfer of a charge .of solidified carbon dioxide. to the pressing chamber.

34, In apparatus for pressing solid carbon dia closure for said discharge of solid carbon dioxide theresition at chamber to the oxide into blocks, in combination, a source of solid carbon dioxide, a pressing cylinder below said source and mounted for movement to and from position raised to said source for receiving a charge of solid carbon dioxide therefrom, a pressing plunger in said cylinder for pressing the solid carbon dioxide charge in the cylinder into a block with the cylinder in raised charge-receiving position, and said pressing cylinder, after the block is formed therein, being movable downwardly from raised position relatively to the plunger 'to cause the plunger to ejectthe completed block from the cylinder.

35. In apparatus for pressing solid carbon dioxide into block form, in combination, a structure providing a solid carbon dioxide receiving chamber having a discharge opening therefrom, a pressing cylinder mounted for movement to and from position receiving a charge of solid carbon dioxide from said chamber discharge opening, fluid pressure actuated means for moving said press cylinder, a pressing plunger in the pressing cylinder and movable therein to press a charge of solid carbon dioxide in the cylinder into a block when the cylinder is in charge-receiving pothe solid carbon dioxide chamber, fluid pressure actuated means for moving said plunger, and said cylinder being movable from charge-receiving position relative to said plunger. to removethe completed block from the cylinder after completion of said block, asource of fluid pressure for said pressure actuated means, and control means for said pressure actuated pressing cylinder and plunger operating means.

. 36. In apparatus for compressing solid carbon from said fluid pressure actuated piston and supported therefrom by spaced rods providing minimum heat conduction paths from the pressure fluid in the cylinder to said low temperature body of solid carbon dioxide.

37. In apparatus for mechanically pressing solid carbon dioxide and the like into blocks, in combination, a source of solid carbon dioxide and the like, a mechanical press movable between normal position spaced from said source for removal of a pressed block from the press without interference from said source and a second position in which it is-in substantially gas-tight relation with the source for receiving a charge therefrom, and means for moving said press between said normal and charging position.

. ADOLPH. SCHUTZ 

